chore: rexport flow_def as flow and cleanup a few example usages (#516)

Author: badmonster0

examples/image_search_example/main.py

@@ -94,7 +94,7 @@ def image_object_embedding_flow(flow_builder: cocoindex.FlowBuilder, data_scope:
 # --- CocoIndex initialization on startup ---
 @app.on_event("startup")
 def startup_event():
-    settings = cocoindex.setting.Settings.from_env()
+    settings = cocoindex.Settings.from_env()
     cocoindex.init(settings)
     app.state.query_handler = cocoindex.query.SimpleSemanticsQueryHandler(
         name="ImageObjectSearch",

examples/product_recommendation/main.py

@@ -61,7 +61,7 @@ class ProductTaxonomyInfo:
     complementary_taxonomies: list[ProductTaxonomy]
 
 @cocoindex.op.function(behavior_version=2)
-def extract_product_info(product: cocoindex.typing.Json, filename: str) -> ProductInfo:
+def extract_product_info(product: cocoindex.Json, filename: str) -> ProductInfo:
     # Print  markdown for LLM to extract the taxonomy and complimentary taxonomy
     return ProductInfo(
         id=f"{filename.removesuffix('.json')}",

python/cocoindex/__init__.py

@@ -2,14 +2,15 @@
 Cocoindex is a framework for building and running indexing pipelines.
 """
 from . import functions, query, sources, storages, cli, utils
-from .flow import FlowBuilder, DataScope, DataSlice, Flow, flow_def, transform_flow
+
+from .auth_registry import AuthEntryReference, add_auth_entry, ref_auth_entry
+from .flow import FlowBuilder, DataScope, DataSlice, Flow, transform_flow
+from .flow import flow_def, flow_def as flow
 from .flow import EvaluateAndDumpOptions, GeneratedField
 from .flow import update_all_flows_async, FlowLiveUpdater, FlowLiveUpdaterOptions
+from .lib import init, start_server, stop, main_fn
 from .llm import LlmSpec, LlmApiType
 from .index import VectorSimilarityMetric, VectorIndexDef, IndexOptions
-from .auth_registry import AuthEntryReference, add_auth_entry, ref_auth_entry
-from .lib import *
 from .setting import DatabaseConnectionSpec, Settings, ServerSettings
 from .setting import get_app_namespace
-from ._engine import OpArgSchema
 from .typing import Float32, Float64, LocalDateTime, OffsetDateTime, Range, Vector, Json